#[non_exhaustive]
pub enum PanelBorderStyle {
Dashed,
Dotted,
Solid,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against PanelBorderStyle
, it is important to ensure
your code is forward-compatible. That is, if a match arm handles a case for a
feature that is supported by the service but has not been represented as an enum
variant in a current version of SDK, your code should continue to work when you
upgrade SDK to a future version in which the enum does include a variant for that
feature.
Here is an example of how you can make a match expression forward-compatible:
# let panelborderstyle = unimplemented!();
match panelborderstyle {
PanelBorderStyle::Dashed => { /* ... */ },
PanelBorderStyle::Dotted => { /* ... */ },
PanelBorderStyle::Solid => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when panelborderstyle
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant PanelBorderStyle::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
PanelBorderStyle::Unknown(UnknownVariantValue("NewFeature".to_owned()))
and calling as_str
on it yields "NewFeature"
.
This match expression is forward-compatible when executed with a newer
version of SDK where the variant PanelBorderStyle::NewFeature
is defined.
Specifically, when panelborderstyle
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on PanelBorderStyle::NewFeature
also yielding "NewFeature"
.
Explicitly matching on the Unknown
variant should
be avoided for two reasons:
- The inner data
UnknownVariantValue
is opaque, and no further information can be extracted. - It might inadvertently shadow other intended match arms.
Variants (Non-exhaustive)§
This enum is marked as non-exhaustive
Dashed
Dotted
Solid
Unknown(UnknownVariantValue)
Unknown
contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl AsRef<str> for PanelBorderStyle
impl AsRef<str> for PanelBorderStyle
source§impl Clone for PanelBorderStyle
impl Clone for PanelBorderStyle
source§fn clone(&self) -> PanelBorderStyle
fn clone(&self) -> PanelBorderStyle
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for PanelBorderStyle
impl Debug for PanelBorderStyle
source§impl From<&str> for PanelBorderStyle
impl From<&str> for PanelBorderStyle
source§impl FromStr for PanelBorderStyle
impl FromStr for PanelBorderStyle
source§impl Hash for PanelBorderStyle
impl Hash for PanelBorderStyle
source§impl Ord for PanelBorderStyle
impl Ord for PanelBorderStyle
source§fn cmp(&self, other: &PanelBorderStyle) -> Ordering
fn cmp(&self, other: &PanelBorderStyle) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere
Self: Sized,
source§impl PartialEq<PanelBorderStyle> for PanelBorderStyle
impl PartialEq<PanelBorderStyle> for PanelBorderStyle
source§fn eq(&self, other: &PanelBorderStyle) -> bool
fn eq(&self, other: &PanelBorderStyle) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd<PanelBorderStyle> for PanelBorderStyle
impl PartialOrd<PanelBorderStyle> for PanelBorderStyle
source§fn partial_cmp(&self, other: &PanelBorderStyle) -> Option<Ordering>
fn partial_cmp(&self, other: &PanelBorderStyle) -> Option<Ordering>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moreimpl Eq for PanelBorderStyle
impl StructuralEq for PanelBorderStyle
impl StructuralPartialEq for PanelBorderStyle
Auto Trait Implementations§
impl RefUnwindSafe for PanelBorderStyle
impl Send for PanelBorderStyle
impl Sync for PanelBorderStyle
impl Unpin for PanelBorderStyle
impl UnwindSafe for PanelBorderStyle
Blanket Implementations§
source§impl<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
source§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.